Radio apparatus



June 16, 1925. 1,542,724

0. l. PRICE RADIO APPARATUS Filed May 31, 1922 v2 Sheets-Sheet 1 l N VENTOR.

/ A TTOBN E Y.

June 16, 1925. 1,542,724

., o. I. PRICE RADIO APPARATUS Filed May 31, 1922 2 Sheets-Sheet 2 l l lI ANT. Cl

. INVENTQR.

BY ATTORNEY.

denser.

Patented June 16, 1925.

UNITEID- STAT-ES PATENT OFFICE.

. RADIO APPARATUS.

.App lication filed May 31, 1922. Seria.l No. 564,734.

To all whomit 'may conce r'nr Be it known that I, Osnoimr: INGLE PRICE,a citizen of the fUnited States residing'at Frederick, in the county-.of Frederick and State of Maryland, have, invented a certain new anduseful Imprpvement{ina Radio Apparatus; of which" .the. vfollowing is -aspecification. 5,;

' This invention elat s. tor'otary: condensers d e Part cula ly oi h fiyr f .'.v f able condenser in 'whicn'a? movable; semi plates is iadaptedtpi ,be adjustably interleaved with: astationary'set of platesin order.to 'suitably va ry the capacity of the con The particular adaptationselected ,for the purpose of illnstration of my invention is its ,use 1in radi'ogflreceiving sets, wherein a plurality of condenser's arecustomarily enrployed, some for, mining thief-receiving, cirul w or senre w t the incom ng gna and others for adciirn latiiig andistoringimpulses of energy for idi s cli ar'ge into a signal i c g. der e-..-.I.;T The objeptlofflth ention is the product er o w r fling-s sempri g. a supporting p l tii selet ng .r e. up Wh meur fe nd s fsahd erelements in a manner'toavoidtlie useiof sulating bushings for' the.prjecting controls, to reduce the number ofgparts of the severalelements (and to; supply I n X ease of adjustment of the parts". A. Afurther, ob'etjoffthe"inyention is the improvement I o Itlie'details ofconstruction of arotary, condenser, and 'the'selection of materialsfortlie I to avoiding the, diingej pt shortcircuiting and the necesityjorgmsulated fbe'aringsi i A further; objec "the, invention is thereductiQnY oflLhe,numberof. parts in rotary condensers 1 with' the,'accomplishment of; an enlarged'ease of movement of the rotatingelements-and the'p'roduction of an increased compactness.

Other objects of the invention will hereinafter appear; in the followingdescription, and the novel features thereof will be particularly pointedout in the appended claims. In-the drawings, in which like referencenumerals indicate likeparts throughout the arts thereoffwith a viewseveral views, Figure 1 is a plan of my improved condenser; Fig. 2 is anelevation thereof; Fig. 3 is a similar view taken at an angle ofdegreesfFig. 4 is a sectional view upon'the line 4'4 oflFigQ 1; Fig. 5is an, elevation of a casingcontaining a radio receiving set with aportion broken away to illustrate the mounting of the'condensers uponthe rear-face of the panel; and Fig. 6 is a front elevation of suchifacasing containing a receiving set. 1

Itwill be-understood thatmy invention is susceptible to "ariousembodiments, and that the form thereof shown and described 'is merelyillustrative.- This embodiment of the invention however has been foundto be practical in construction and operation,' for which reason I haveadopted it "asfmy preferred form.

The invention may be said to ,comprise, first, the provision in a radioreceiving set for receiving instrument of a panel, face of insulatingmaterial upon the backof which is mounted elements "forming therecelv'lng set insuch a manner as to avoid'fthe use of specialinsulators, secondly, the production of a frame for a condenserele'mentembodying portionsof insulating material, whereby the necessityfor -insulated bushings and special provision for the insulating of theparts is avoided; and thirdly, the improve- ,mentof the details ofconstruction of a rotary condenser whereby a "minimum number of parts isrequired and a special case of operation and compactness areaccomplished.,' p

These features will now be described in detailand their individualfunctions pointed out, after which a recital of the beneficialresultsdue to their conjoint use will be n- .f Referring to Figs. 5 and6, the numeral 10 indicates a casing of wood supported by the feet orknobs 11, preferably of rubber, upon any suitable surface. The front orface 12 of the casing is made of a sheet'of stiff insulating material,upon the back of which is mounted the several elements of a radioreceiving set. I have preferred to illustrate my invention in connectionwith a panel of bakelitc. This panel 12 is provided with in alignmentwith 'eaehother for movement withthe spindle iir'its rotation; "It isnecessary int-heuse-ofa devie'of this type to have the spindle with theplates mounted thereon remain at any desired position: To accomplishthis result I have provided a spring 38 whiclr'isattached to theunderface of the plate 19 by the screw 39 and having its bifurcated end40 bearing upon the shoulder 31 formed between the reduced end of thespindle and the screw threaded portion. The pressure of the spring produces the necessary frictional engagementof the collar 29 with the rearface of the end plate 18.

The spindle and the sleeves 33 establish the electric conductivitybetween the series of rotary plates, and the spring 38 is the meansemployed to conduct the current from the spindle 28. Any suitableelectrical terminal may be provided for the projecting end of the screw39 for the attachment of a lead wire. Electric conductivity isestablished between the several stationary plates by means of the posts20 and the sleeves 24, and current may be conducted thereto through anysuitable terminal attached to the end of one of the posts. I have shownfor this purpose the sheet metal clip 41 to which the wire may besoldered.

From the foregoing description the operation of the condenser elementwill be apparent as well as the mode of assembling its parts, sincethese parts were described in the order of their emplacement. Thereremains to complete a full disclosure of invention only a recital of theconjoint use of the several details of construction;

The provision of an insulating panel and the mounting of an element of aradio set upon such panel by means of screws passing into an insulatedportion of the element frame work avoids any danger of shortcircuitingby reason of the mounting. It will be appreciated that the screws 21 donot touch any metal parts as their ends lie between the collar 29 andthe edge of the recessed portion of the stationary plate 22, and theirheads are protected by the knob 31. The provision of a frame work forthe condenser composed of insulated front and rear plates obviates thenecessity of providing special insulation for a metal frame element andpermits the plate 22 to lie in contact with the frame parts. Theapertures in the bakelite end members form eflicient bearings for thespindle 27. The ends of the posts 20 are imbedded in the plate 18 andhave their extremities abutting the panel 12; they are consequentlyfully protected and the arrangement acts as the equivalent of a nut lockfor the posts. The spring 38 while producing the necessary friction forposition holding also serves as an electrical conductor between thespindle 27 and thetern'iifnal 39-. ltlwiltbe appreciated thatthe-details of construction produce an"e':' tremel-y compact condenserwith a reduced number" of parts and-'a-sp'ecial ability"- tolle mountedin an efficient manner anecuy ape the rearfaeeofthe panel 12 with the"full area of the plate- 18 in contact with said panel.

What I claim is:

1. A variable condenser arranged to be mounted immediately adjacent anoperating panel comprising in combination a set of stationary plates anda set of rotatable plates, :1 frame for mounting said stationary platesin spaced relation, said frame consisting of a pair of semi-circular endplates of flat insulating material angled on one edge thereof, aplurality of posts extending between said end plates with one of saidstationary plates lying directly in contact with one of said end plates,and the others of said stationary plates equally spaced from each otherupon said posts, and a shaft journaled directly in the angled portionsof said insulated end plates and carrying said rotatable plates inposition between said stationary plates, one of said flat end platesproviding a surface for engagement with securing means extending throughsaid operating panel.

2. A variable condenser arranged to be mounted immediately adjacent anoperating panel comprising in combination a set of stationary plates anda set of rotatable. plates, a frame for mounting said stationary platesin spaced relation, said frame consisting of a pair of semi-circular endplates of fiat insulating material angled on one edge thereof, aplurality of posts extending be tween said end plates with one of saidstationary plates lying directly in contact with one of said end plates,and the others of said stationary plates equally spaced from each otherupon said posts, a rotary spindle iournalled directly in the angledport-ions of said insulated end plates and comprising a collar at oneend lying in contact with one end plate, a shoulder at the opposite endof said spindle formed by reducing the end thereof,

a leaf spring attached to the second end plate and having a bifurcatedend'straddling said reduced spindle and producing frictional engagementbetween said collar and first end plate whereby said rotary 'pindle maybe revolved to various positions and set with respect to said end plateswhen one of said end plates is secured directly adjacent said operatingpanel.

3. A variable condenser comprising in combination a framework consistingof front and rear plates of insulating material substantiallysemi-circular in contour bounded by an angled edge, connecting poststerminating in said insulated plates. stationary plates mounted on saidconnectti l ing posts and spaced one from another with and carryingmovable plates arranged to be one of saidplates lying directly incontact rotated with said spindle in a horizontal with theinner face ofsaid front plate plane with said front insulated plate formthroughoutthe area thereof, bearing apering the sole support for said condenserwith i tures positioned directly adjacent the anreference to an adjacentsurface.

gled edges of said insulating plates, a rotating. spindle mounted insaid apertures OSBORNE I. PRICE.

